Tin's Heme II Set - 36,37,38,40,41,42

1. What is the most common acquired bleeding disorder?

a. Trauma-induced coagulopathy

b. Vitamin K deficiency

c. Liver disease

d. VWD

a. Trauma-induced coagulopathy

2. Which is a typical form of anatomic bleeding?

a. Epistaxis

b. Menorrhagia

c. Hematemesis

d. Central nervous system bleed

d. Central nervous system bleed

3. What factor becomes deficient early in liver disease, and what assay does its deficiency prolong?

a. Prothrombin deficiency, the PT

b. Factor VII deficiency, the PT

c. FVIII deficiency, the PTT

d. Factor IX deficiency, the PTT

b. Factor VII deficiency, the PT

4. Which of the following conditions causes a prolonged thrombin time?

a. Antithrombin deficiency

b. Prothrombin deficiency

c. Hypofibrinogenemia

d. Warfarin therapy

c. Hypofibrinogenemia

5. In what type or subtype of VWD is the RIPA test result positive when ristocetin is used at a concentration of less than 0.5 mg/mL?

a. Subtype 2A

b. Subtype 2B

c. Subtype 2N

d. Type 3

b. Subtype 2B

6. What is the typical treatment for vitamin K deficiency when the patient is bleeding?

a. Vitamin K and plasma

b. Vitamin K and four-factor PCC

c. Vitamin K and platelet concentrate

d. Vitamin K and FVIII concentrate

b. Vitamin K and four-factor PCC

7. If a patient has anatomic soft tissue bleeding and poor wound healing, but the PT, PTT, TT, platelet count, and platelet functional assay results are normal, what factor deficiency is possible?

a. Fibrinogen

b. Prothrombin

c. Factor XII

d. Factor XIII

d. Factor XIII

8. What therapy may be used for a hemophilic boy who is bleeding and who has a high FVIII inhibitor titer?

a. rFVIIa

b. Plasma

c. Cryoprecipitate

d. FVIII concentrate

a. rFVIIa

9. What is the most prevalent form of VWD?

a. Type 1

b. Type 2A

c. Type 2B

d. Type 3

a. Type 1

10. Which of the following assays is used to distinguish vitamin K deficiency from liver disease?

a. PT

b. Protein C assay

c. Factor V assay

d. Factor VII assay

c. Factor V assay

11. Mucocutaneous hemorrhage is typical of:

a. Acquired hemorrhagic disorders

b. Localized hemorrhagic disorders

c. Defects in primary hemostasis

d. Defects in fibrinolysis

c. Defects in primary hemostasis

22. The coagulation factors having a sex-linked recessive inheritance pattern are

A. Factor V and factor VIII

B. Factor VIII and factor IX

C. Factor IX and factor X

D. von Willebrand factor and factor VIII

B. Factor VIII and factor IX

2. Which test result would be normal in a patient with dysfibrinogenemia?

A. Thrombin time

B. APTT

C. PT

D. Immunologic fibrinogen level

D. Immunologic fibrinogen level

2. D The level of plasma fibrinogen determined immunologically is normal. In a patient with dysfibrinogenemia, fibrinogen is not polymerized properly, causing abnormal fibrinogen-dependent coagulation tests.

3. A patient with a prolonged PT is given intravenous vitamin K. The PT corrects to normal after 24 hours. What clinical condition most likely caused these results?

A. Necrotic liver disease

B. Factor X deficiency

C. Fibrinogen deficiency

D. Obstructive jaundice

D. Obstructive jaundice

3. D Obstructive jaundice contributes to coagulation disorders by preventing vitamin K absorption. Vitamin K is fat soluble and requires bile salts for absorption. Parenteral administration of vitamin K bypasses the bowel; hence the need for bile salts.

5. A prolonged APTT is corrected with factor VIII- deficient plasma but not with factor IX-deficient plasma. Which factor is deficient?

A. V

B. VIII

C. IX

D. X

C. IX

5. C Because the prolonged APTT is not corrected with a factor IX-deficient plasma, factor IX is suspected to be deficient in the test plasma.

6. Which of the following is a characteristic of classic hemophilia A?

A. Prolonged bleeding time

B. Autosomal recessive inheritance

C. Mild to severe bleeding episodes

D. Prolonged PT

C. Mild to severe bleeding episodes

6. C Hemophilia A (factor VIII deficiency) is characterized by mild to severe bleeding episodes, depending upon the concentration of factor VIII:C. Hemophilia A is inherited as a sex-linked disease. Bleeding time and prothrombin time are both normal in hemophilia A

7. Refer to the following results: PT = prolonged APTT = prolonged Platelet count = decreased Which disorder may be indicated?

A. Factor VIII deficiency

B. von Willebrand's disease

C. DIC

D. Factor IX deficiency

C. DIC

7. C In DIC, there is a diffuse intravascular generation of thrombin and fibrin. As a result, coagulation factors and platelets are consumed, resulting in decreased platelet count and increased PT and APTT.

8. Which of the following is a predisposing condition for the development of DIC?

A. Adenocarcinoma

B. Idiopathic thrombocytopenic purpura (ITP)

C. Post-transfusion purpura (PTP)

D. Heparin-induced thrombocytopenia (HIT)

A. Adenocarcinoma

8. A Adenocarcinoma can liberate procoagulant (thromboplastic) substances that can activate prothrombin intravascularly. ITP is a thrombocytopenia caused by an autoantibody; PTP is an alloimmune thrombocytopenia caused by transfusion of blood or blood products; HIT results from an antibody to heparin-PF4 complex causing thrombocytopenia in 1%-5% of patients who are on heparin therapy. In some affected persons, thrombosis may also occur.

9. Factor XII deficiency is associated with:

A. Bleeding episodes

B. Epistaxis

C. Decreased risk of thrombosis

D. Increased risk of thrombosis

D. Increased risk of thrombosis

9. D Factor XII-deficient patients commonly have thrombotic episodes. Factor XII is the contact activator of the intrinsic pathway of coagulation. It also plays a major role in the fibrinolytic system by activating plasminogen to form plasmin. Hemorrhagic manifestations are not associated with factor XII deficiency because thrombin generated by the extrinsic pathway can activate factor XI to XIa, and factor VIIa/TF can activate factor IX to IXa

10. The following results were obtained on a patient: normal platelet count and function, normal PT, and prolonged APTT. Which of the following disorders is most consistent with these results?

A. Hemophilia A

B. Bernard-Soulier syndrome

C. von Willebrand's disease

D. Glanzmann's thrombasthenia

A. Hemophilia A

10. A Hemophilia A is associated with the deficiency of factor VIII resulting in bleeding and an abnormal APTT. The platelet number and function are normal in this disorder. Von Willebrand's disease is a disorder of platelet adhesion associated with decreased VWF and factor VIII, causing an abnormal platelet function test and an abnormal APTT test. Both Glanzmann's thrombasthenia and Bernard-Soulier syndrome cause deficient platelet aggregation, but do not cause an abnormal APTT

11. The following laboratory results were obtained from a 40-year-old woman: PT = 20 sec; APTT = 50 sec; thrombin time = 18 sec. What is the most probable diagnosis?

A. Factor VII deficiency

B. Factor VIII deficiency

C. Factor X deficiency

D. Hypofibrinogenemia

D. Hypofibrinogenemia

11. D Fibrinogen (factor I) is a clotting protein of the common pathway and is evaluated by the thrombin time. In hypofibrinogenemia (fibrinogen concentration <100 mg/dL), the PT, APTT, and TT are prolonged. In factor VII deficiency, the APTT is normal; in factor VIII deficiency, the PT is normal; and in factor X deficiency, the TT is normal.

13. The most suitable product for treatment of factor VIII deficiency is:

A. Fresh frozen plasma

B. Factor VIII concentrate

C. Prothrombin complex concentrate

D. Factor V Leiden

B. Factor VIII concentrate

13. B Factor VIII concentrate (human or recombinant) is the treatment of choice for patients with factor VIII deficiency. Fresh frozen plasma contains factor VIII; however, it is no longer used as the primary treatment for factor VIII deficiency. Prothrombin complex concentrate is used to treat patients with factor VIII inhibitor.

14. Which of the following is associated with an abnormal platelet aggregation test?

A. Factor VIII deficiency

B. Factor VIII inhibitor

C. Lupus anticoagulant

D. Afibrinogenemia

D. Afibrinogenemia

14. D Fibrinogen is a plasma protein that is essential for platelet aggregation and fibrin formation. In afibrinogenemia, platelet aggregation is abnormal.

16. Which results are associated with hemophilia A?

A. Prolonged APTT, normal PT

B. Prolonged PT and APTT

C. Prolonged PT, normal APTT

D. Normal PT and APTT

A. Prolonged APTT, normal PT

16. A Hemophilia A is associated with factor VIII deficiency. Factor VIII is a factor in the intrinsic coagulation pathway that is evaluated by the APTT and not the PT test. The PT test evaluates the extrinsic and common pathways.

18. Which of the following is associated with multiple factor deficiencies?

A. An inherited disorder of coagulation

B. Severe liver disease

C. Dysfibrinogenemia

D. Lupus anticoagulant

B. Severe liver disease

18. B Most of the clotting factors are made in the liver. Therefore, severe liver disease results in multiple factor deficiencies. An inherited disorder of coagulation is commonly associated with a single factor deficiency. Lupus anticoagulant is directed against the phospholipid-dependent coagulation factors. Dysfibrinogenemia results from an abnormal fibrinogen molecule

19. Normal PT and APTT results in a patient with a poor wound healing may be associated with:

A. Factor VII deficiency

B. Factor VIII deficiency

C. Factor XII deficiency

D. Factor XIII deficiency

D. Factor XIII deficiency

19. D Factor XIII deficiency can lead to impaired wound healing and may cause severe bleeding problems. Factor XIII is a fibrin stabilizing factor that changes the fibrinogen bonds in fibrin polymers to stable covalent bonds. Factor XIII is not involved in the process of fibrin formation and, therefore, the PT and APTT are both normal

20. Fletcher factor (prekallikrein) deficiency may be associated with:

A. Bleeding

B. Thrombosis

C. Thrombocytopenia

D. Thrombocytosis

B. Thrombosis

20. B Fletcher factor (prekallikrein) is a contact factor. Activated prekallikrein is named kallikrein and is involved in activation of factor XII to XIIa. Like factor XII deficiency, Fletcher factor deficiency may be associated with thrombosis.

21. One of the complications associated with a severe hemophilia A is:

A. Hemarthrosis

B. Mucous membrane bleeding

C. Mild bleeding during surgery

D. Immune-mediated thrombocytopenia

A. Hemarthrosis

21. A In severe hemophilia A, factor VIII activity is less than 1%, resulting in a severe bleeding diathesis such as hemarthrosis (bleeding into the joints).

22. The most common subtype of classic von Willebrand's disease is:

A. Type 1

B. Type 2A

C. Type 2B

D. Type 3

A. Type 1

22. A VWF is a multimeric plasma glycoprotein that results in different subtypes of von Willebrand's disease with varied severity. The most common subtype is subtype 1, and 70%-80% of these cases are associated with mild bleeding. Subtype 3 involves the total absence of the von Willebrand's molecule and is associated with severe bleeding. Subtypes 2A and 2B result in deficiency of intermediate and/or high molecular weight portions of the von Willebrand molecule and are associated with 10%-12% and 3%-6% of cases of von Willebrand's disease, respectively

23. A prolonged APTT and PT are corrected when mixed with normal plasma. Which factor is most likely deficient? A. VIII B. V C. XI D. IX

23. B Factor V (common pathway factor) deficiency is most likely suspected, because both the PT and APTT are prolonged, and both are corrected when mixed with normal plasma

18. Which of the following factors is associated with hemophilia B?

a. Factor VIII

b. Factor IX

c. Factor XI

d. Fibrinogen

b. Factor IX

18. b. A deficiency of factor IX is called hemophilia B. Hemophilia A is associated with a deficiency of factor VIII. Hemophilia C is associated with a deficiency of factor XI.

32. Which of the following results would be expected in a patient with dysfibrinogenemia?

a. Normal PT, normal aPTT, prolonged thrombin time

b. Abnormal PT, normal aPTT, prolonged thrombin time

c. Abnormal PT, abnormal aPTT, normal thrombin time

d. Normal PT, normal aPTT, normal thrombin time

a. Normal PT, normal aPTT, prolonged thrombin time

32. a. In dysfibrinogenemia, the structure of fibrinogen is abnormal. Fibrin still forms, resulting in normal PT and PTT evaluations. As a result of the structural abnormality, the thrombin time that assesses fibrinogen to fibrin formation is affected.

34. The following results were obtained from a patient who recently underwent major surgery.

PT=Prolonged

APTT=Prolonged

Fibrinogen=Decreased

D-Dimer=Positive

Platelet count=Decreased

Which of the following conditions is likely?

a. Fibrinogenolysis

b. Fibrinogen deficiency

c. Disseminated intravascular coagulation

d. Vitamin K deficiency

c. Disseminated intravascular coagulation

34. c. Disseminated intravascular coagulation is a disorder of consumption. Coagulation proteins, including fibrinogen, and platelets are all consumed in thrombi, resulting in a prolongation of the prothrombin time (PT) and partial thromboplastin time (PTT) and decreased fibrinogen and platelet count. The D-dimer is significant and can help rule out other conditions, because it indicates that thrombi are being formed. The D-dimer would be negative in fibrinogenolysis, fibrinogen deficiencies, and vitamin K deficiency. In vitamin K deficiencies, the fibrinogen assay, platelet count, and D-dimer assay would be normal.

46. The following test results were obtained on a patient who is being seen for easy bruising.

Bleeding time=Increased

PT=Normal

aPTT=Prolonged (mix with normal pooled plasma corrected aPTT)

Platelet count=Normal

ADP, collagen, epinephrine platelet aggregation=Normal

Ristocetin platelet aggregation=Absent

Which of the following conditions is expected?

a. Hemophilia A

b. Hemophilia B

c. Von Willebrand's disease

d. Factor XII deficiency

c. Von Willebrand's disease

46. c. von Willebrand's disease is a qualitative platelet disorder. In this condition, the platelet aggregation response to ristocetin is abnormal. The bleeding time is increased as a result of the qualitative defect in the platelets. Although von Willebrand factor (vWF) is not assessed in the partial thromboplastin time (PTT) assay, vWF also carries around factor VIII in the circulation to protect it from degradation. Therefore a decrease in vWF sometimes results in a prolongation of the PTT assay because of the lower factor VIII levels, which are corrected by the addition of normal pooled plasma.

362. The 2 factors that differentiate liver disease from vitamin K deficiency are:

a. II and VII

b. IX and VII

c. VIII and IX

d. V and VII

d. V and VII

365. A hemophiliac male and a normal female can produce a:

a. female carrier

b. male carrier

c. male hemophiliac

d. normal female

a. female carrier

366. Hemophilia B is a sex-linked recessive disorder that presents with a decrease in factor:

a. VIII

b. IX

c. X

d. XI

b. IX

369. Acute disseminated intravascular coagulation is characterized by:

a. hypofibrinogenemia

b. thrombocytosis

c. negative D-Dimer

d. shortened thrombin time

a. hypofibrinogenemia

370. A patient develops unexpected bleeding and the following text results were obtained:

PT and aPTT prolonged

fibrinogen decreased

D-dimer increased

platelets decreased

What is the most probable cause of these results?

a. familial afibrinogenemia

b. primary fibrinolysis

c. DIC

d. liver disease

c. DIC

371. A patient presents with the following results:

test results reference range

thrombin 48 seconds 12-21 seconds

reptilase time 38 seconds 14-22 seconds

These results are characteristic of:

a. dysfibrinogenemia

b. increased D-dimer

c. fibrin monomer-split product complexes

d. therapeutic heparinization

a. dysfibrinogenemia

373. Only an abnormal aPTT would be seen in the following disorder:

a. deficiencies of factor X, V, and II

b. disseminated intravascular coagulation

c. liver disease

d. anti-factor VIII antibodies

d. anti-factor VIII antibodies

383. Occasional spontaneous bleeding may occur in hemophiliac who is classified as:

a. severe

b. mild

c. moderate

d. all of the above

c. moderate

385. Alloantibodies are found in:

a. congenital hemophilia

b. acquired hemophilia

c. congenital von Willebrand disease

d. acquired von Willebrand disease

a. congenital hemophilia

390. A 48 year old male is screened pre-operatively. He has a positive family history for bleeding. The patient is of Ashkenazi Jewish descent. His results are as follows:

test result ref. range

PT 11.5s 10.5-13.5 s

aPTT 45.1s 25-35 sec

1:1 mixing study pt=28.1s pooled plasma=29s

Based on this history and the results of these tests, this patient's most likely diagnosis is a deficiency in factor:

a. VIII

b. IX

c. XI

d. XII

c. XI

393. A patient presents with a factor VIII level of 2%. The vWF acitivity (ristocestin cofactor) is <1% with a vWF antigen of 3%. The most likely diagnosis is:

a. hemophilia A

b. hemophilia B

c. type II vWD

d. type III vWD

d. type III vWD

Two children in the same family have recurrent, chronic bruising in multiple sites, repeated long-lasting epistaxis, and minor bleeding after dental work. Which type of disorder is most likely?

a. Localized, acquired, anatomic

b. Localized, congenital, anatomic

c. Generalized, congenital, systemic

d. Generalized, acquired, systemic

c. Generalized, congenital, systemic

Which is appropriate initial testing for the siblings with recurrent, chronic bruising in multiple sites, repeated long-lasting epistaxis, and minor bleeding after dental work?

a. Fibrinogen, D-dimer, and platelet aggregation studies

b. Factor VIII assay, liver function tests, and vitamin K level

c. von Willebrand factor (VWF) antigen, Bethesda titer, and reptilase time

d. Prothrombin time (PT), partial thromboplastin time (PTT), and platelet count

d. Prothrombin time (PT), partial thromboplastin time (PTT), and platelet count

What is the possible mechanism for bleeding in patients with severe liver disease?

a. Thrombocytopenia

b. Inadequate production of procoagulants

c. Disseminated intravascular coagulation (DIC)

d. All of the options

d. All of the options

Which is decreased in DIC?

a. Fibrinogen

b. PT

c. PTT

d. Fibrin degradation products

a. Fibrinogen

(Fibrinogen is decreased in DIC. The PT and PTT are both increased (prolonged), whereas fibrin degradation products are increased)

The bleeding associated with renal disease is related most to defective:

a. blood vessels.

b. plasma procoagulants.

c. platelets.

d. inhibitors.

c. platelets.

(Platelet dysfunction is the primary cause for prolonged bleeding in patients with renal failure)

Which patient group is most susceptible to bleeding because of a deficiency of vitamin K-dependent proteins?

a. Those with poor diets

b. Those on antibiotic agents

c. Pregnant women

d. Newborns

d. Newborns

Clot-based mixing studies and Bethesda titers are used to test for:

a. vitamin K deficiency

b. inhibitors (antibodies) against coagulation factors

c. DIC

d. hemophilia

b. inhibitors (antibodies) against coagulation factors

(An inhibitor against a coagulation protein is confirmed using clot-based mixing studies. The Bethesda titer is then performed to determine the concentration of the inhibitor)

What are the primary roles of VWF?-

a. Mediates platelet adhesion and carrier molecule for factor VIII.

b. Mediates platelet aggregation and carrier molecule for factor IX.

c. Inhibits excess coagulation and activates protein C.

d. Activates plasmin and enhances vitamin K factors.

a. Mediates platelet adhesion and carrier molecule for factor VIII.

(VWF is required for normal platelet adhesion; it is also the carrier protein for factor VIII, protecting it from proteolysis and thus prolonging the in vivo half-life from just a few minutes (in the absence of VWF) to 8 to 12 hours)

A 21-year-old woman has a primary complaint of menorrhagia. Her coagulation screen gives the following results:

PT= 12.0 secs (RI= 11-15 secs)

PTT= 40 secs (RI= 25-37 secs)

Factor VIII activity- 35% (RI= 50-150%)

Plt count= 225 x 10^9/L (RI= 150-400 x 10^9/L)

What disorder is most likely?

a. Hemophilia A

b. Hemophilia B

c. VWD, type 1

d. Factor X deficiency

c. VWD, type 1

(VWD is the most prevalent of the congenital bleeding disorders, affecting both female and male subjects; hemophilia A and B both affect primarily male subjects. Female patients with VWD often complain of menorrhagia. Most patients with VWD have factor VIII levels in the range of 35% to 50%.)

Desmopressin acetate (DDAVP) is used to treat:

a. dysfibrinogenemia.

b. warfarin overdose.

c. vitamin K deficiency.

d. VWD, type 1.

d. VWD, type 1.

(DDAVP, which triggers the release of VWF from storage organelles, is used to treat type 1 VWD. It is also useful in type 2A, but it is contraindicated in type 2B)

What is common in patients with severe hemophilia A?

a. Generalized bleeding after trauma or dental work

b. Generalized hemorrhage

c. Major bruising on extremities and chronic nosebleeds

d. Serious anatomic bleeds into joints

d. Serious anatomic bleeds into joints

Which test is increased in a patient with severe hemophilia A?

a. PTT

b. Thrombin time (TT)

c. PT

d. Factor VIII assay

a. PTT

(The PTT is increased (prolonged) in patients with severe hemophilia A because of a significant decrease in factor VIII. The PT and TT are both normal)

What test is useful for detection of a female carrier of hemophilia A?

a. PTT

b. PT

c. Factor VIII to VWF ratio

d. VWF antigen test

c. Factor VIII to VWF ratio

(90% are detected using this ratio. This is because VWF production is unaffected by factor VIII deficiency, so it should be normal in a female hemophilia A carrier, whereas the factor VIII activity will be less than that of VWF. Thus a discrepancy exists in the concentration of these two proteins)

What is the purest form of factor VIII that is available for treating a bleeding patient with hemophilia A?

a. Cryoprecipitate

b. Recombinant factor VIII concentrate

c. Fresh frozen plasma

d. Factor VIII concentrate prepared by chemical concentration

b. Recombinant factor VIII concentrate

What is the best test to distinguish hemophilia A from B or C?

a. Specific factor assays

b. PTT

c. TT

d. Bleeding time

a. Specific factor assays

(Hemophilia A (factor VIII deficiency), hemophilia B (factor IX deficiency), and hemophilia C (factor XI deficiency) are differentiated from one another using specific factor assays)

In which substance is a patient with the following coagulation test results most likely deficient?

PT= 17 secs (RI= 11-15 secs)

PTT= 31 secs (RI= 25-37 secs)

TT= 16 secs (RI= 15-21 secs)

a. Fibrinogen

b. Factor VII

c. Factor VIII

d. Factor X

b. Factor VII

(Factor VII deficiency shows a prolonged PT with a normal PTT result. It is apart of the extrinsic pathway in which PT measures. A deficiency of fibrinogen ideally should prolong the PT, PTT, and TT. Factor VIII deficiency prolongs the PTT but not the PT and TT, whereas a factor X deficiency should prolong both the PT and PTT but not the TT)

The urea solubility test is used to detect deficiencies in which factor?

a. Fibrinogen

b. Factor V

c. Factor XII

d. Factor XIII

d. Factor XIII

(The plasma from patients with a factor XIII deficiency forms weak clots that dissolve within 2 hours when suspended in a 5M urea solution because the clot has not been cross-linked by XIIIa)

What coagulation screening test is the most sensitive for detecting mild liver disease?

a. Fibrinogen

b. PTT

c. PT

d. TT

c. PT

(Liver disease particularly affects production of the vitamin K-dependent proteins. Because the PT is sensitive to factor VII activity and it (factor VII) has a short half-life of 3 to 5 hours, the PT is the most sensitive for detecting mild liver disease)

Which protein is the best test to distinguish moderate to severe liver disease from vitamin K deficiency?

a. Factor V concentration

b. Factor VII concentration

c. Factor VIII concentration

d. Factor IX concentration

a. Factor V concentration

(Factor V is not vitamin K dependent, but it is produced in the liver, so it is decreased in moderate to severe liver disease. Factors VII and IX are both vitamin K dependent, so they are decreased in both liver disease and vitamin K deficiency. Factor VIII is not decreased in either liver disease or vitamin K deficiency; in fact, because it is an acute phase reactant, it may actually be elevated in mild to moderate liver disease)

A 67-year-old woman arrives at the emergency department with acute bleeding into the back of the throat. A coagulation screen is ordered with the following results:

PT= 12 secs (RI= 11-15 secs);

PTT= 57 secs (RI= 25-37 secs) and 1:1 mix with normal plasma is 36 secs (immediate);

Fibrinogen= 450 mg/dL (RI= 150-400 mg/dL)

What would be a reasonable next step to perform?

a. Perform factor IX assay.

b. Perform factor VII assay.

c. Incubate the 1:1 mix at 37°C for 1 hour.

d. Perform TT.

c. Incubate the 1:1 mix at 37°C for 1 hour.

(Factor VIII autoantibodies are usually time and temperature dependent. Thus the 1:1 mix must be incubated at 37°C for 1 to 2 hours to give the antibody time to react with the factor VIII added by the normal plasma. Prolongation of the PTT on this incubated 1:1 mix indicates that an antibody to VIII is present. A factor VIII assay, when performed, will show a low factor VIII (less than 30%)

What procedure is used to quantitate a factor VIII inhibitor?

a. Bethesda assay

b. Reptilase time

c. Factor VIII concentration

d. VWF assay

a. Bethesda assay

All can mask a deficiency of VWF and thus of type 1 VWD except:

a. fibrinogen levels.

b. pregnancy.

c. acute stress.

d. type ABO blood group.

a. fibrinogen levels.

(The concentration of VWF is low in VWD, type 1. VWF is an acute-phase reactant and is thus elevated in acute stress. Higher estrogen levels during pregnancy also elevate VWF. Individuals with type ABO blood type have higher levels of VWF. All these can thus mask VWD)

A 39-year-old male patient shows evidence of poor wound healing and a history of joint bleeding. What protein deficiency is most likely present?

a. Factor VIII

b. Factor IX

c. Factor V

d. Factor XIII

d. Factor XIII

(Patients with a deficiency of factor XIII have evidence of poor wound healing and anatomic bleeds)

Which screening test would be normal when the plasma for the patient with a deficiency of factor XIII is analyzed?

a. PT

b. PTT

c. T

d. All of the options

d. All of the options

(The PT, PTT, and TT are all normal in a patient with factor XIII deficiency. Factor XIII deficiency is evaluated by placing the clot in 5M urea; the uncross-linked clot is weak and dissolves within 2 hours in this solution)

The clinical presentation of platelet-related bleeding may include all of the following except:

a. Bruising

b. Nosebleeds

c. Gastrointestinal bleeding

d. Bleeding into the joints (hemarthroses)

d. Bleeding into the joints (hemarthroses)

A defect in GP IIb/IIIa causes:

a. Glanzmann thrombasthenia

b. Bernard-Soulier syndrome

c. Gray platelet syndrome

d. Storage pool disease

a. Glanzmann thrombasthenia

Aspirin ingestion blocks the synthesis of:

a. Thromboxane A2

b. Ionized calcium

c. Collagen

d. ADP

a. Thromboxane A2

Patients with Bernard-Soulier syndrome have which of the following laboratory test findings?

a. Abnormal platelet response to arachidonic acid

b. Abnormal platelet response to ristocetin

c. Abnormal platelet response to collagen

d. Thrombocytosis

b. Abnormal platelet response to ristocetin

Which of the following is the most common of the hereditary platelet function defects?

a. Glanzmann thrombasthenia

b. Bernard-Soulier syndrome

c. Storage pool defects

d. Multiple myeloma

c. Storage pool defects

A mechanism of antiplatelet drugs targeting GP IIb/IIIa function is:

a. Interference with platelet adhesion to the subendothelium by blocking of the collagen binding site

b. Inhibition of transcription of the GP IIb/IIIa gene

c. Direct binding to GP IIb/IIIa

d. Interference with platelet secretion

c. Direct binding to GP IIb/IIIa

The impaired platelet function in myeloproliferative neoplasms results from:

a. Abnormally shaped platelets

b. Extended platelet life span

c. Increased procoagulant activity

d. Decreased numbers of alpha- and dense granules

d. Decreased numbers of a- and dense granules

Which is a congenital qualitative platelet disorder?

a. Senile purpura

b. Ehlers-Danlos syndrome

c. Henoch-Schönlein purpura

d. Waldenström macroglobulinemia

b. Ehlers-Danlos syndrome

In uremia, platelet function is impaired by higher than normal levels of:

a. Urea

b. Uric acid

c. Creatinine

d. NO

d. NO

The platelet defect associated with increased paraproteins is:

a. Impaired membrane activation owing to protein coating

b. Hypercoagulability owing to antibody binding and membrane activation

c. Impaired aggregation because the hyperviscous plasma prevents platelet-endothelium interaction

d. Hypercoagulability because the increased proteins bring platelets closer together, which leads to inappropriate aggregation

a. Impaired membrane activation owing to protein coating

A reduction in thrombin generation in patients with Scott syndrome results from:

a. Defective granule secretion

b. Altered platelet aggregation

c. Altered expression of phospholipids on the platelet membrane

d. Deficiency of vitamin K-dependent clotting factors

c. Altered expression of phospholipids on the platelet membrane

Thrombocytopenia associated with the use of cardiopulmonary bypass is not caused by:

a. Anti-GP IIb/IIIa antibodies

b. Hemodilution

c. Platelet binding to bypass circuitry

d. Platelet consumption associated with normal postsurgical hemostatic activity

a. Anti-GP IIb/IIIa antibodies

1. The qualitative platelet disorders and vascular disorders typically exhibit what type of

symptoms?

a. superficial bleeding

b. deep tissue bleeding

c. hemarthrosis

d. thrombosis

ANS: A

Superficial bleeding, including petechiae, purpura, epistaxis (nose bleeds), and gingival (gum)

bleeding, is characteristic of qualitative bleeding disorders.

DIF: Cognitive Level: 1 REF: page 740

2. Which of the following is a disorder with absent platelet glycoprotein Ib/IX/V and in which

the patient has moderate thrombocytopenia, large platelets, and normal aggregometry with all

agents except ristocetin?

a. von Willebrand disorder (VWD)

b. Bernard-Soulier syndrome

c. Glanzmann thrombasthenia

d. dense granule deficiency

ANS: B

Patients with Bernard-Soulier syndrome have deficient glycoprotein Ib/IX/V receptors on

their surface. This is inherited as an autosomal recessive disorder; heterozygotes are normal or

near normal, but homozygotes have (usually) a low platelet count and enlarged platelets.

Aggregation is normal with all agonists except ristocetin.

DIF: Cognitive Level: 1 REF: pages 742-743

3. Which of the following is the most likely diagnosis for a patient with a normal platelet count

and no aggregation with any agent except ristocetin?

a. aspirin ingestion

b. gray platelet syndrome

c. vitamin C deficiency

d. Glanzmann thrombasthenia

ANS: D

Patients with Glanzmann thrombasthenia have a normal platelet count and prolonged bleeding

time. Their platelets do not aggregate with any agonist except ristocetin.

DIF: Cognitive Level: 1 REF: page 742

4. Which of the following is the most common cause of acquired platelet dysfunction?

a. myeloproliferative disorders

b. Wiskott-Aldrich syndrome

c. drugs, especially aspirin

d. afibrinogenemia

ANS: C

Aspirin and other drugs are the most common causes of acquired platelet dysfunction.

DIF: Cognitive Level: 1 REF: page 748

5. Which of the following is normal in a patient regularly taking aspirin?

a. platelet aggregation

b. platelet cyclooxygenase function

c. synthesis of thromboxane A2

d. platelet count

ANS: D

Only the platelet count, of those evaluations listed, is normal in a patient who regularly takes

aspirin. Aspirin acetylates cyclooxygenase, which is necessary for the synthesis of

thromboxane A2.

DIF: Cognitive Level: 1 REF: page 749

6. What types of hemostatic complications are found in patients with myeloproliferative

disorders?

a. hemorrhagic

b. thrombotic

c. abnormal platelet function

d. all of the above

ANS: D

Patients with one of the chronic myeloproliferative disorders, such as polycythemia vera and

essential thrombocythemia, may have abnormal platelet function; clinically, they may result in

either abnormal bleeding or abnormal thrombosis. Some patients develop both, although this

is rare.

DIF: Cognitive Level: 1 REF: page 751

7. What is the mechanism for the platelet dysfunction in multiple myeloma and Waldenström

macroglobulinemia?

a. Granules become deficient.

b. Platelets are coated with paraprotein.

c. Nitric oxide is not produced.

d. Cyclooxygenase is acetylated.

ANS: B

In both of these disorders, a high concentration of a monoclonal protein is present in

circulation. This is called a paraprotein, and it can coat platelets, interfering with surface

receptors, leading to their dysfunction.

DIF: Cognitive Level: 1 REF: page 752

8. All of the following are common conditions or situations that interfere with platelet function

except

a. liver disease

b. uremia

c. allergic purpura

d. cardiopulmonary bypass surgery

ANS: C

Allergic purpura does not interfere with platelet function. All of the other listed conditions or

situations can affect platelet function.

DIF: Cognitive Level: 1 REF: page 755

9. Which of the following is true regarding testing for the diagnosis of vascular disorders?

a. Most do not have abnormal clinical laboratory tests.

b. The platelet count and aggregometry are useful.

c. The prothrombin time (PT) and partial thromboplastin time (PTT) are most useful.

d. Evaluation of von Willebrand factor (VWF) is useful.

ANS: A

Clinical laboratory tests are not available for evaluation and diagnosis of vascular disorders.

Ruling out other sources of bleeding disorders often makes the diagnosis. The usual clinical

signs are easy bruising and spontaneous bleeding, especially from mucosal surfaces. In that

respect they are similar to platelet dysfunction disorders.

DIF: Cognitive Level: 2 REF: page 753

10. A 78-year-old patient recently noticed dark blotches on his forearms and on the backs of his

hands. He seems to bruise even when a phlebotomy is performed using excellent technique

with no problems encountered. No other symptoms exist, and all laboratory tests are normal.

Which of the following is the most likely diagnosis?

a. hereditary hemorrhagic telangiectasia

b. Ehlers-Danlos syndrome

c. paraproteinemia and amyloidosis

d. senile purpura

ANS: D

Senile purpura is the most likely diagnosis for this 78-year-old man who only recently began

to notice abnormal bruising and/or bleeding. The hereditary abnormalities would have

presented earlier in life. Paraproteinemia and amyloidosis would demonstrate other abnormal

clinical laboratory testing.

DIF: Cognitive Level: 3 REF: page 755

11. Platelet count and function studies are performed on a patient with a history of easy bruising,

and the following results are obtained:

Test Result

Platelet count 295 x 10^9/L

Platelet function assay Prolonged

Platelet aggregation with epinephrine Primary but no secondary wave

Platelet aggregation with low-dose adenosine

diphosphate (ADP)

Primary but no secondary wave

Platelet aggregation with ristocetin Normal

What is the most likely diagnosis for this patient?

a. Bernard-Soulier disease

b. dense granule deficiency

c. Glanzmann thrombasthenia

d. gray platelet syndrome

ANS: B

The platelet count on this patient is normal; however, the platelet function assay is abnormal,

which suggests platelet dysfunction. Of the disorders listed, only dense granule deficiency has

the platelet aggregation results that are listed. Patients with Bernard-Soulier disease have

normal aggregation studies with every agonist except ristocetin, which is abnormal. The

reverse is true for Glanzmann thrombasthenia: they have normal aggregation with ristocetin

but have no primary wave, as well as no secondary wave with other agonists. Patients with

gray platelet syndrome have a moderate thrombocytopenia, prolonged bleeding time, and

large platelets that appear gray on a Wright-stained blood film because of the absence of

-granules. Platelet aggregation studies are unremarkable.

DIF: Cognitive Level: 3 REF: pages 745-746

12. Clopidogrel (Plavix) is a drug used therapeutically for patients with a risk of arterial thrombi

because it

a. inhibits thrombin.

b. activates the protein C pathway.

c. inhibits platelet function.

d. activates plasminogen.

ANS: C

Clopidogrel is an antiplatelet function drug used for three reasons: (1) to treat patients with

arterial occlusive disease; (2) for prevention of myocardial infarction; and (3) to decrease the

risk of thrombotic stroke in patients with cerebrovascular disease and in patients who are

intolerant of aspirin.

DIF: Cognitive Level: 1 REF: page 750